Modern Physics Letters A

Fiducial production cross-section measurements of Standard Model processes, in principle, provide constraints on new physics scenarios via a comparison of the predicted Standard Model cross-section and the observed cross-section. This approach received significant attention in recent years, both from direct constraints on specific models and the interpretation of measurements in the view of effective field theories. A generic problem in the reinterpretation of Standard Model measurements is the corrections application of to data to account for detector effects. These corrections inherently assume the Standard Model to be valid, thus implying a model bias of the final result. In this work, we study the size of this bias by studying several new physics models and fiducial phase–space regions. The studies are based on fast detector simulations of a generic multi-purpose detector at the Large Hadron Collider. We conclude that the model bias in the associated reinterpretations is negligible only in specific cases, however, typically on the same level as systematic uncertainties of the available measurements.

The existence and mysterious nature of sterile neutrinos are revolutionizing physics from the particle level to the cosmological scales. The recent results from the MiniBooNE experiment at Fermi-lab observed far more ${\nu }_e$ appearance than expected, which have provided a hint about the possible existence of sterile neutrinos. The results, if confirmed in future experiments, will have significant implications for cosmology and astroparticle physics. This will require new neutrino mass models to accommodate these additional degrees of freedom. In respect to that, this work is just an extension of our recent work toward the CP phase analysis of Quark-Lepton Complementarity (QLC) model in a $3+1$ scenario. The parametrization of CKM₄ and PMNS₄ using Monte Carlo Simulation is used to estimate the texture of nontrivial correlation matrix $(V_{c_4})$. As such, we have successfully investigated the constrained values for sterile neutrino parameters, and also predicted the values for Dirac CP-Violation phase and the CP re-phasing invariant $(J)$. The results obtained are consistent with the data available from various experiments, like No$\nu$A, MINOS, SuperK and IceCube-DeepCore. Furthermore, this analysis would be very important in view of growing sterile neutrino experiments.

Through the Kaluza–Klein theory, we investigate the quantum dynamics of a Klein–Gordon particle under the Aharonov–Bohm effect for bound states, where it is subject to the linear and Coulomb-type central potentials inserted in the Klein–Gordon equation by modification of the mass term. Then, we determine analytically solutions of bound states and the energy profile of the scalar particle in this background.

In this paper, we look for AdS solutions to generalized gravity theories in the bulk in various spacetime dimensions. The bulk gravity action includes the action of a non-minimally coupled scalar field with gravity, and a higher-derivative action of gravity. The usual Einstein–Hilbert gravity is induced when the scalar acquires a nonzero vacuum expectation value. The equation of motion in the bulk shows scenarios where AdS geometry emerges on-shell. We further obtain the action of the fluctuation fields on the background at quadratic and cubic orders.

In this paper, we evaluate the fine-structure constant variation that should take place as the pseudo-Riemannian Universe expands and its curvature is changed adiabatically. Such variation of the fine-structure constant is attributed to an energy loss by an extended physical system (consisting of baryonic component and electromagnetic (EM) field) due to expansion of our Universe. Obtained ratio $\dot{\alpha }/\alpha =1\cdot 10^{-18}$ (per second) is only five times smaller than actually reported experimental limit on this value. For this reason, the obtained variation can probably be measured within a couple of years. To argue the correctness of our approach, we calculate the Planck constant as adiabatic invariant of the EM field propagated on the pseudo-Riemannian manifold characterized by slowly varied geometry. Finally, we discuss the double clock experiment based on Al${}^{+}$ and Hg${}^{+}$ clocks carried out by Rosenband et al. (Science 2008). We show that in this case (when the fine-structure constant is changed adiabatically), the method based on double clock experiment cannot be applied to measure the fine-structure constant variation.

For a perfect fluid source, we have investigated the homothetic matter collineations (HMCs) of locally rotationally symmetric (LRS) Bianchi type V spacetimes. For degenerate energy–momentum tensor, two cases arise. In one case, the solution of HMC equations yields 11-dimensional algebra of HMCs while in the second case, we have infinite number of HMCs. When the energy–momentum tensor is non-degenerate, we have four cases, each giving five-dimensional algebra of HMCs. Some LRS Bianchi type V metrics are provided admitting HMCs.

The aim of this paper is to find proper conformal vector fields of some Bianchi type II spacetimes in the f(R) theory of gravity using direct integration technique. In this study, seven cases have been discussed. Studying each case in detail, it is shown that the spacetimes under consideration do not admit proper conformal vector fields. Conformal vector fields are either homothetic vector fields or Killing vector fields.

In this work, we investigate the relativistic quantum dynamics of spin-0 particles in the background of (1 + 2)-dimensional Gürses spacetime [M. Gürses, Class. Quantum Grav. 11, 2585 (1994)] with interactions. We solve the Klein–Gordon equation subject to Cornell-type scalar potential in the considered framework, and evaluate the energy eigenvalues and corresponding wave functions, in detail.

We have calculated astrophysical reaction cross-sections for $(\gamma ,\alpha )$ reactions of some nuclei important for the calculation of p-process reaction-decay network. Reaction rates for $\alpha$-induced reactions are calculated with the semi-microscopic optical potential constructed using double folding method, where nuclear density distributions for finite nuclei along with the effective nucleon–nucleon interaction are the important components of the folded potential. For this purpose, density distributions of target nuclei are obtained from relativistic mean field approach. Astrophysical reaction cross-section for elastic scattering of $\alpha$-particle from ${}^{92}\mathrm{\text{Mo}}$ target is compared with the existing experimental results to constrain the newly formed potential. Further, to check the credibility of the present theoretical framework, the astrophysical S-factor for $(\alpha ,\gamma )$ reactions are compared with the experimental observation, wherever available. Finally, an estimate of dominant photodisintegration channels at various astrophysical temperature is discussed for p-nuclei ${}^{74}\mathrm{\text{Se}}$ and ${}^{96}\mathrm{\text{Ru}}$.

Perfect state transfer can be achieved between two marked vertices of graphs like a star graph, a complete graph with self-loops and a complete bipartite graph, and two-dimensional Lattice by means of discrete-time quantum walk. In this paper, we investigate the quality of quantum state transfer between two marked vertices of an unsymmetrical graph like the butterfly network. Our numerical results support the conjecture that the fidelity of state transfer depends on the quantum state to be transferred dynamically. The butterfly network is a typical example studied in networking coding. Therefore, these results can provide a clue to the construction of quantum network coding schemes.